Field
The present disclosure relates to electronic circuits and, more particularly, to inductor-based resonators for voltage controlled oscillators.
Background
Voltage controlled oscillator (VCO) phase noise is often a major contributor to the overall phase noise in circuits utilizing an electronic oscillator such as phase locked loop (PLL) circuit. Conventional VCO designs may require significant power and area to meet typical specifications of wireless communication systems. The presence of higher harmonic components in an active transconductance (gm) device can cause a frequency drift of an inductor-capacitor (LC) tank resonance if the LC tank impedance at the higher harmonics is not high. This phenomenon, named the Groszkowski effect, is a contributor to noise in LC VCOs. Any technique that improves phase noise, while at the same time does not consume large area and power, is desirable.